How the Windows Time service treats a leap second (909614)


The information in this article applies to:

  • Microsoft Windows Server 2003, Standard Edition
  • Microsoft Windows Server 2003, Datacenter Edition
  • Microsoft Windows Server 2003, Enterprise Edition
  • Microsoft Windows XP Professional
  • Microsoft Windows XP Home Edition
  • Microsoft Windows 2000 Professional
  • Microsoft Windows 2000 Advanced Server
  • Microsoft Windows 2000 Server

INTRODUCTION

This article describes how the Windows Time service treats a leap second.

MORE INFORMATION

When the Windows Time service is working as a Network Time Protocol (NTP) client

The Windows Time service does not indicate the value of the Leap Indicator when the Windows Time service receives a packet that includes a leap second. (The Leap Indicator indicates whether an impending leap second is to be inserted or deleted in the last minute of the current day.) Therefore, after the leap second occurs, the NTP client that is running Windows Time service is one second faster than the actual time. This difference is resolved at the next time synchronization.

When the Windows Time service is working as an NTP server

No method exists to include a leap second for the Windows Time service.

How a leap second is included depends on NTP server settings.
Modification Type:MinorLast Reviewed:11/16/2005
Keywords:kbinfo KB909614 kbAudGeneralUser
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